Liquid ejecting heads that causes pressure fluctuation In liquid in a pressure chamber and thereby discharges the liquid from nozzle openings in the form of liquid drops include, for example, ink jet recording heads used in image forming apparatuses such as printers, color material ejecting heads used for manufacturing color filters of liquid crystal displays, electrode material ejecting heads used for forming electrodes of organic EL (Electro Luminescence) displays and FEDs (field emission displays), and bioorganic matter ejecting heads used for manufacturing biochips. There are various types of such liquid ejecting heads.
For example, some ink jet recording heads (hereinafter referred to as “recording head”) for an ink jet recording apparatus (hereinafter referred to as “printer”) includes a head unit and a case member (head case). The head unit includes a flow path unit, a nozzle plate, an actuator unit, and so forth. The flow path unit includes continuous liquid flow paths leading to nozzle openings via pressure chambers. The nozzle plate includes a plurality of aligned nozzle openings communicate with the liquid flow paths. The actuator unit includes pressure generating elements capable of changing the capacities of the pressure chambers. The case member is formed of a resin. To the case member are fixed the head unit and an introduction needle holder (a base). The introduction needle holder includes liquid introduction needles that introduce liquid in a liquid holding member into liquid flow paths communicating with the pressure chambers.
In such recording heads, when the introduction needle holder and the case member are joined, a packing member and a wiring substrate are interposed between these members, the packing member connecting the liquid flow paths, the wiring substrate supplying a drive signal to the actuator unit, and then flange portions extending from the case member is screwed at three locations to the introduction needle holder (see, for example, JP-A-2004-74676).